Rabble for roasting-furnaces.



PATENTED SEPT. 13, 1904.

2 SHEETS-SHEET 1.

M. CORCORAN.

RABBLE POR ROASTING FURNAGES.

APPLICATION FILED APR. zo, 1904.

No MODEL.

.1 "Il/ mm/ Y WIN/M W/ w, ...MW H lllmlllsll www W m a a my w a No. 769,689. PATBNTED SEPT. 13, 1904. M. CORCORAN.

RABBLB POR ROASTING PURNACES.

APPLIGATION FILED APB. zo, 1904.

No MODEL. 2 SHEETS-SHEET 2.

.EioL/g. 2 5

@Q ffy Mm d@ UNITED STATES Patented September 13, 1904.

PATENT OFFICE.

RABBLE FOR ROASTlNG-FURNACES.

SPECIFICATION forming part of Letters Patent No. 769,689, dated September 13, 1904.

Application tiled April 20, 1904. Serial No. 204,029. KNO model.)

To LM wiz/0m, it may concern.'

Be it known that I, MICHAEL CoRCoRAN, of Anaconda, in the county of Deerlodge and State of Montana, have invented certain new and useful Improvements in Rabbles for Roasting-Furnaces; and I hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, which form part of this specification.

My invention relates to rabbles for use in calcining or roasting furnaces and the like, and has for one of its salient objects to provide a construction whereby the wearing parts or blades of the rabble are made renewable with a minimum waste of material.

A further object of my invention is to provide a construction such that the removable renewable blades may be locked in their proper positions in their supporting structures without the employment of bolts or other retaining devices.

A further object of my invention is to generally improve the construction of devices of the character described.

vWith a view to attaining these and other objects which will become apparent to those skilled in the art from a consideration of the following description my invention consists in the features of construction and arrangement of parts specified in the claims and hereinafter more fully set forth.

In the drawings I have illustrated my invention as embodied ina roasting or calcining furnace of the well-known McDougal type.

In such drawings, Figure l is a vertical cross-section of a series of superposed liearths of such a furnace equipped with rabbles enibodying my invention. Fig. 2 is atop view of one of the carrying-plates detached. Fig. 3 is a bottom view of said plate. Fig'. 4 is an end view of the plate. Fig. 5 is a bottom view of a modified form of plate. Fig. 6 is a side elevation of a blade detached. Figs. T and 8 are end views taken, respectively,

from the left and right ends of Fig. 6. Fig.

to like scale.

arm, taken from its outer end; and Fig. 12

is an end View of the arm from its inner end. Throughout the drawings like characters of reference indicate always like parts.

The McDougal roaster, as well known, comprises an exterior casing A and superposed transverse liearths B, alternate liearths throughout being provided with materialpassages b', arranged centrally of the liearths, and the intervening alternate liearths being provided with material-passages b2, disposed near the outer or peripheral edge thereof. C represents a rotatable bearing-shaft extending vertically and centrally of the casing A and provided with spreading rabble-arms or stirring-arms 15, two of such arms being usually provided for each hearth and the arms in adjacent liearths being arranged at right angles to each other. Each of these arms carries a series of blades or teeth inclined to move the ore toward the passage communicating with the next subjacent hearth. D represents a water-piping system arranged within the hollow shaft and arms to cool the same. The general construction of this device forrns no part of my present invention and is chosen as simply illustrative of a construction wherein my invention may be advantageously embodied; but the features of my invention I will now describe.

Upon the arms 15 I removably mount independent rabble-blades so constructed that the upright portion or blade proper may be removed froin its supporting structure, so that when renewal of the blades is requisite only the blades proper need be removed and replaced, thereby avoiding the removal of any part of the support upon which little wear is imposed by the action of the device. Furthermore, I so shape and mount the removable blades aforesaid that they are held in their positions upon their supports by binding action due to their pressure upon the rnaterial being rabbled, thereby avoiding the necessityl of using extraneous fastening means in securing them in place. To secure these results, my invention contemplates so constructing the blades and their supporting devices that they interengage in such manner for operation.

that the blades are detachably held in position upon the supporting devices and so shaping the interengaging parts and positioning the blades that the action of the blades on the ore under treatment serves to hold the blades tightly in their proper positions.

-In the specific construction illustrated the rabble-arm 15 is provided with parallel laterally-extending base-fianges 16, longitudinally coeXtensive with said arms 15.

17 indicates a plate, preferably of metal, provided on its upper surface with inturned flanges 18, adapted to overlie and engage the fianges 16 of the rabble-arm 15, so that such plate is supported beneath the arm. The under side of said plate 17 is provided with a guideway 19, suitably formed thereon and preferably dovetail-shaped in cross-section and tapered longitudinally throughout its length. The iange 18 of the plate 17, which 'is to lie forward in the direction of travel of the rotating rabble-arm, is preferably provided with strengthening-ribs 20, extending' down the front of the fiange and inward under the plate a short distance, said ribs being disposed out of alinement with the guide 19, so as not to interfere with the insertion or removal of blades into or from said guides.

21 indicates a `rabble-blade. (Best illustrated in Figs. 6 to 8.) Such blade may be made of metal, fire brick, slag composition, or any other suitable material and is provided at its upper end with means for engaging in the guide 19 of the carrier-plate 17. Such means in the present illustration comprises a head 22, of dovetail cross-section and tapering width, vadapted to accurately interfit with the dovetailed guide 19 of the carrier-plate.

The angle of inclination of the guide 19 to the direction of travel of the plate 17 when in use in the roaster may of course be varied to suit requirements, but preferably the angle of inclination and the direction of taper of the guide 19 are such that when a blade 21 is in place therein and is moved in the direction of its movement during the operation of the machine resistance opposed to the said movement will drive the blade toward the narrow end of its guide 19, thereby wedging it more and more tightly in position therein. By so constructing and proportioning the devices I am enabled to avoid the necessity of employing extraneous fastening means to secure the blades in position in their carrying-plates.

In assembling, a series of carrier-plates 17 may be slipped'upon the flanges 16 of rabblearms 15 and the end plates secured in any de- -sired manner to prevent the line of plates from slipping. These parts togetherl constitute the supporting structure for the blades. Blades 2l may then be inserted in the guides 19 of the carrier-plates, and the device is ready As alternate rabble-arms must have their blades disposed at opposite angles to properly direct the ore under treatment, it is necessary where each carrier-plate is provided with only one guide 19 to employ two different sets of carrier-plates having their guides inclined at opposite angles. The plates cannot be simply reversed for the reason that the larger ends of the guides 19 should always be presented forward with reference to the direction of movement of the arm. If desired, therefore, the carrier-plate may be made as illustrated in Fig. wthat is to say. said plate may be provided with two intersecting guides 19, arranged at opposite angles and both having their larger ends fronting in the direction in which the plate is to travel in operation.

Obviously such a plate might be used in any one of the hearths, the blades being set in whichever of the guides would enable said blades to move the material under treatment in the proper direction toward or from the center of the furnace.

It will be apparent that when the rabblesV to renew the worn parts with the least possi-V ble waste of material, as. the plates 17 last much longer than the blades 21.

Vhile I have described my invention as embodied in a particular form of furnace, I do not desire to be understood as limiting its useful application thereto, as it will be apparent that the principle of my invention might be applied for many purposes without departing from its spirit and scope. It will also be apparent that, if desired, the plates 17 might be omitted and the guides 19 formed in any suitable manner on the lower surface of the arms 15 themselves or that the guide and head might be reversed, the blade providing the guide and the plate having the head formed thereon; but I prefer to employ the construction herein described. Furthermore, it will be obvious that, if desired, instead of employing a series of individual carrier-plates 17, each with a guide 19, a single elongated plate having a plurality of guides 19 might be used.

` Other variations in the specific application of my invention may be readily made by those skilled in the art without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim, and 'desire to secure by Letters Patent of the United States, is-

1. In a device of the character described a supporting structure and a blade, one of said .IOO

IIO

members being provided with a longitudinally-tapering guide, and the other said member being provided with a correspondinglytapering head intertitting in said guide.

2. In a device of the character described, a supporting structure having' a tapered dovetailed guide, and a blade provided with a head interlitting in said guide.

In a device of the character described an arm provided at its lower edge with lateral base-flanges, a carrier-plate provided with flanges arranged to engage the base-flanges of the arm whereby said carrier-plate may be slid upon said arm, and a blade,`the blade and carrier-plate being provided one with a guide and the other with a head adapted to engage said guide, whereby the blade may be slid into position in the carrier-plate.

In a device of the characterdescribed, an arm, a carrierplate having' a head-and-guide engagement with said arm, a blade having a head-andguide engagement with the carrierplate, the blade-engaging member on the carrier-plate being dis posed atan inclination relative to the arm.

In a device of the character described, a supporting structure adapted to travel in a delinite direction provided with a guide inclined relative to said direction of travel, and tapering in a direction opposite to said direction of travel, in combination with a blade adapted to engage said guide to be retained thereby.

6. In a device of the character described, a supporting structure adapted/to travel in denite direction, provided with two guides disposed at opposite angles to said direction of travel and both tapering in a direction opposite to the direction of travel, in combination with a blade adapted to intel-tit in either of said guides.

T. In a device of the character described, an arm provided with laterally-extendingflanges, a blade-carrying plate provided with anges adapted to overlic the Hanges of the arm, and strengthening-ribs extending' in front of and under one of said flanges.

In testimony that I claim the Vforegoing as my own I atlix my signature in presence of two witnesses.

MICHAEL CORCORAN. In presence of- RnUnN G. COLLINS, W'ILLIAM E. NVILsoN. 

